Airplane



July 23, 1935. c. H. CONGDON AIRPLANE Original Filed Nov. 15, 1923gnwnloz C. If C oxvc poxv Reiuued July 23, 1935 UNITED STATES PATENTOFFICE Serial No. 674,995, November 15. 1923.

Application for reissue November 1, 1933, Serial No.

16 Ciaima. (Cl. 244-12) (Granted under the act of March 8, 18815 asamended April 30, 1928; 370 0. G. 757) This invention relates toimprovements in airplanes and more particularly to the construction ofairplane wings whereby the lateral control of airplanes at low speedsand high angles of attack may be increased.

One of the objects of the present invention is to provide a simple andpractical mechanism of the above general character which may beinexpensively manufacturedjassembled and installed.

A further object is to provide a flap mechanism for airplane wingsadapted to spoil the lift and increase the drag on the up aileron sideof the machine and thereby increase the lateral control of the machineat low speeds and high angles of attack.

Other objects will be in part obvious and in part hereinafter pointedout in connection with the accompanying sheet of drawing.

Figure 1 is a transverse, partial, sectional and diagrammatic viewshowing the invention as applied to an airplane wing in full lineposition and in dotted line position when operated.

Figure 2 is a plan view of a portion of the wing.

Referring now to the drawing in detail, 6 denotes the lower surface ofan airplane wing of standard construction and 8 the upper surfaceextending between two beams I positioned longitudinally of the wing andat the rear there is provided the usual hinged aileron I hinged to therear beam 1 at the point lli whereby it may be swung upwardly ordownwardly as indicated by the dotted line position. 'Along the forwardedge of the wing is mounted the nose flap I I normally occupying aposition in a longitudinal recess whereby its upper surface is flushwith and conforms to the upper surface of the wing. This flap is hingedat the point I! and is provided with a pivotally connected link II, oneend of which is connected with a second pivot link ll secured by a pivotii to a suitable bracket it, the links l3 and II together forming atoggle normally held in restricted position by means of spring IT.

Extending rearwardly of the machine is a link II, the rear end of whichis pivoted at 20 to an aileron horn 2i in such a manner that as thetoggle i3-ll is moved to extended position the nose flap Ii will bemoved upwardly as shown by its dotted line position and simultaneouslythe aileron will also be moved. There is, however, a certain amount oflost motion and definite ratio of movement whereby the aileron may bemoved a certain extent without moving the nose flap. Upon the wing, andextending beyond the contour thereof, is a relatively narrow taperinghood through which the rod it extends into the interior of the wing.Perhaps this can be better explained by a brief statement of theoperation which is as follows.

As above stated the operating mechanism for the nose flap ll acts, inthe specific instance 5 shown, against the resistance of spring llconnected to the toggle links and push rod it which extends rearwardlyto the aileron horn. The relation between the horn and the push rod orlink it is such that when the aileron is 5 above normal, or the firstdotted line position shown in Figure 1, the horn will come in contactwith the push rod and any further movement of the aileron towards the 30or upper dotted line position will force the nose flap upproportionately. Ratio of the linkage is such that movement of theaileron, by any of the well known operative connections therefor, fromthe 5 position to the 30 position downwardly from the full line positionshown in Fig. 1, will produce substantially no movement of the noseflap, therefore, it will be seen that the nose flap only comes intooperation when the aileron moves upwardly above the 5 position and doesnot function when the aileron moves downwardly and consequently thecontour of the wing will not be broken and there will be no disturbanceof the air flow thereover. In other words, the flap mechanism isdesigned to spoil the lift and increase the drag on the up aileron sideof the machine and consequently increase the lateral control of themachine at slow speeds and high angles of attack.

It will thus be seen that the present invention provides a reliable andefliclent mechanism adapted to accomplish, among others, all of theobjects and advantages herein set forth.

Without further analysis, the foregoing will so fully reveal the gist ofthis invention that others can by applying current knowledge readilyadapt it for various applications without omitting certain featuresthat, from the standpoint of the prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this invention,and, therefore, such adaptations should and are intended to becomprehended within the 45 meaning and range of equivalence of thefollowing claims.

The invention herein described may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

What I claim isi 1. In an airplane wing construction, in combination, aflap on the upper surface of the wing and slightly to the rear of theforward edge thereof, a

predetermined point.

3. In an airplane wing construction, in combination,

or said flap, connections between said flap and aileron involving a lostmotion connection whereairplane wing construction, bination, a movableflap extending adjacent the forward edge of the wing, a trailing aileronrearwardly of said flap, connections between said flap tour 01 the wing,rigid brackets secured to the beam within the contour of the wing,

to which brackets said flap is hinged.

10. The combination 01' claim 8 characterized by at least one of saidbrackets having a rigid portion supporting a portion of the connectingmeans.

11. The combination of by a beam extending across the front portion ingsaid flap, said beam and to gle jointed levers is pivoted.

12. The combination of, claim ot the wing and adapted to be moved tochange of the wing,

16. In an airplane, the combination of a wing, 7|

a nose flap movably mounted on the lace and near the wing, said todecrease the lift on new the forward edge 0! one slde o! flap normallybeing. adapted not its side or the wins. an

5 aileron movably mounted on and trailing trom the rear edge normallybeing of one side of the wing, said aileron adapted not to substantiallyincrease the drag on its side of the wing. and means for movingsuccessively from thelr normal positlons first the alleron and then theflap for mcreasing the drag and decreasing the hit on one side of themachine at low speed and large angles of attack on the wlng.

cum H. OONGDON.

